Numerical Modeling of Brittle Mineral Foam in a Sacrificial Cladding Under Blast Loading

Cellular materials, such as mineral foams, have proven to be excellent energy absorbents. They can be used as crushable core in sacrificial cladding (SC) for blast mitigation. In this study, the blast absorption capability of a brittle mineral foam-based SC is investigated through finite element modeling using the LS-DYNA software. The SC consisted of a thin aluminum plate clamped into a rigid steel frame. The blast load was generated by 25 g of TNT equivalent. The blast absorption capability of the considered SC was evaluated by comparing the maximum out-of-plane displacement of the center of the plate subjected to
a blast load with and without the brittle mineral foam. The presence of the brittle mineral foam reduces the maximum out-of-plane displacement of the center of the plate at least by a factor two. The brittle mineral foam is modeled both in solid elements and smoothed-particle hydrodynamics (SPH) with Fu Chang’s constitutive material law based exclusively on the results of quasi-static compression tests of the foam and a phenomenological relation between stress and strain rate. The numerical model with SPH predicts the maximum displacement of the center of the aluminum plate obtained experimentally
with an average relative error of 5%.